It is known to be desirable to load a trailer at an elevation close to the ground so that no unnecessary lifting or auxiliary ramps are required. When loading a motorcycle, use of ramps involves a risk of the motorcycle tipping over during loading which can be dangerous to the operator due to the potentially elevated height of the ramp and the trailer onto which the motorcycle is loaded.
Various prior art examples of trailers are disclosed in the following patents.
U.S. Pat. No. 3,860,255 belonging to Rodriguez discloses a lift trailer in which a load carrying deck of the trailer can be lowered substantially to ground level by releasing the deck frame from the wheeled frame upon which the hitch is fixed by raising the hitch upwardly to be spaced well above the deck frame in a loading position. Accordingly the hitch must be uncoupled from a towing vehicle in order to load the trailer which can be awkward and cumbersome in some instances.
U.S. Pat. No. 6,520,521 belonging to Mayfield and U.S. Pat. No. 2,577,246 belonging to Hill disclose trailers in which a deck frame for supporting a load thereon includes the hitch fixedly coupled at a front end thereof with the rear being supported on a wheeled frame which can be pivoted into a raised position relative to the deck frame to effectively lower the rear of the deck frame to the ground for loading. In each instance however the fixed connection of the hitch at the front of the trailer does not permit the entire deck frame to be lowered to the ground unless the hitch is uncoupled from a towing vehicle and is also permitted to be placed on the ground.
U.S. Pat. No. 4,673,328 belonging to Shiels, U.S. Pat. No. 4,077,643 belonging to Bates and European application 0 245 104 A2 disclose further examples of trailers in which a deck frame upon which a load is arranged to be supported can be lowered relative to the surrounding wheeled frame however a complex mechanism is required in each instance to raise and lower the deck frame relative to the wheeled frame resulting in an increased potential for failure. Furthermore failure of the lift mechanism which raises the deck frame into the transport position can result in the deck frame dangerously falling during transport.